Infants exposed to air pollution from traffic may be at risk of reduced lung function, according to a Swedish study that adds to evidence of adverse effects air quality can have on children’s respiratory health.

More than 1,900 Swedish children were followed from birth to age 8 in the study. They were periodically given questionnaires about their health and were given lung function and allergy tests. The researchers also estimated the amount of pollution in the air close to each child’s home, day care, and school.

Higher concentrations of air pollution from road traffic were associated with poorer lung function in children by the time they reached age 8, the study found. Young boys and children with asthma were at particular risk for lower lung function.

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Air pollution did not seem to affect lung function in infants after their first year of life, suggesting that longer term exposure may bring on the negative effects.

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BOTTOM LINE: Infants exposed to air pollution from traffic may be at risk of reduced lung function.

CAUTIONS: The researchers only calculated accurate air pollution concentration levels once, and estimated the levels in subsequent years. The researchers did not assess air pollution levels indoors, which may also contribute to the development of lower lung function.

WHERE TO FIND IT: American Journal of Respiratory and Critical Care Medicine, Oct. 12

The HPV vaccine does not raise risk for sexual activity

Adolescent girls who get the human papillomavirus (HPV) vaccine are not more likely to engage in sexual activity, according to a new study.

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HPV is the most common sexually transmitted virus and some strains can lead to oral and genital cancers. The US Centers for Disease Control and Prevention and the American Academy of Pediatrics recommend HPV vaccine for girls and boys as young as age 11.

Researchers from Emory University in Atlanta reviewed electronic health records of nearly 1,400 girls ages 11 and 12 between July 2006 and December 2010, looking at whether they received at least one dose of the vaccine within the first year, and whether they were later counseled about contraception, had acquired a sexually transmitted disease, or had become pregnant.

The nearly 500 girls who received at least one dose of the vaccine were no more likely to be diagnosed with a sexually transmitted disease, discuss contraception, or become pregnant compared with the nearly 900 girls who did not get the vaccine, the study found.

BOTTOM LINE: HPV vaccine does not lead to increased sexual activity among adolescent girls.

CAUTIONS: The study is based on the assumption that girls who engage in sexual activity would seek care for a sexually transmitted disease, ask for contraception, or become pregnant.